Methods: A total of 191 athletes were assessed during the preseason for factors predictive of noncontact LAS. The baseline measurements included weightbearing dorsiflexion range of motion (ROM), leg-heel angle, foot internal rotation angle in plantar flexion, classification according to the mortise test, and navicular-medial malleolus (NMM) distance. Occurrence of noncontact LAS and participation in practice and games were prospectively recorded for 11 months.

Results: Of the 191 athletes assessed, 169 (145 males, 24 females) completed the study; 125 athletes had a history of ankle sprain. During the observational period, 16 athletes suffered noncontact LAS (0.58 per 1000 athlete-exposures) consisting of 4 initial sprains and 12 recurrences. The hazard ratio estimated by a Cox regression analysis showed that athletes with an NMM distance ≥4.65 cm were 4.14 times more likely to suffer an initial noncontact LAS than were athletes with a shorter NMM distance (95% confidence interval, 1.12-14.30) and that athletes with a weightbearing dorsiflexion ROM >49.5° were 1.12 times as likely to suffer a recurrent noncontact LAS compared with athletes with a lower ROM (95% confidence interval, 1.05-1.20).

Mentions:
The measurements taken from the 125 athletes with a previous ankle sprain were used in a Cox regression analysis of the injury and control groups, which demonstrated that weightbearing dorsiflexion ROM was predictive of a recurrent noncontact LAS (Table 3). The hazard ratio estimate indicated that athletes with a weightbearing dorsiflexion ROM greater than 49.5° were 1.12 times as likely to suffer a recurrent noncontact LAS as athletes with a lower ROM (95% CI, 1.05-1.20) (Table 4). Figure 5 shows the survival curve based on the weightbearing dorsiflexion ROM. Because the cut-off value of weightbearing dorsiflexion ROM was 49.5° (sensitivity, 0.75; specificity, 0.86) by a receiver operating characteristic curve (Figure 6), and the average weightbearing dorsiflexion ROM in this study and the previous large prospective study was 45° ± 4°,27 the athletes’ outcomes were categorized into 3 groups according to their weightbearing dorsiflexion ROM: group 1, <41° (50 athletes); group 2, 41° to 49.5° (50 athletes); and group 3, >49.5° (25 athletes). Group 2 exhibited the highest survival rate (100.0%), followed by group 1 (94.0%) and group 3 (64.0%), where “survival” is defined as free from ankle sprain.

Mentions:
The measurements taken from the 125 athletes with a previous ankle sprain were used in a Cox regression analysis of the injury and control groups, which demonstrated that weightbearing dorsiflexion ROM was predictive of a recurrent noncontact LAS (Table 3). The hazard ratio estimate indicated that athletes with a weightbearing dorsiflexion ROM greater than 49.5° were 1.12 times as likely to suffer a recurrent noncontact LAS as athletes with a lower ROM (95% CI, 1.05-1.20) (Table 4). Figure 5 shows the survival curve based on the weightbearing dorsiflexion ROM. Because the cut-off value of weightbearing dorsiflexion ROM was 49.5° (sensitivity, 0.75; specificity, 0.86) by a receiver operating characteristic curve (Figure 6), and the average weightbearing dorsiflexion ROM in this study and the previous large prospective study was 45° ± 4°,27 the athletes’ outcomes were categorized into 3 groups according to their weightbearing dorsiflexion ROM: group 1, <41° (50 athletes); group 2, 41° to 49.5° (50 athletes); and group 3, >49.5° (25 athletes). Group 2 exhibited the highest survival rate (100.0%), followed by group 1 (94.0%) and group 3 (64.0%), where “survival” is defined as free from ankle sprain.

Bottom Line:
The baseline measurements included weightbearing dorsiflexion range of motion (ROM), leg-heel angle, foot internal rotation angle in plantar flexion, classification according to the mortise test, and navicular-medial malleolus (NMM) distance.The hazard ratio estimated by a Cox regression analysis showed that athletes with an NMM distance ≥4.65 cm were 4.14 times more likely to suffer an initial noncontact LAS than were athletes with a shorter NMM distance (95% confidence interval, 1.12-14.30) and that athletes with a weightbearing dorsiflexion ROM >49.5° were 1.12 times as likely to suffer a recurrent noncontact LAS compared with athletes with a lower ROM (95% confidence interval, 1.05-1.20).NMM distance predicts initial noncontact LAS, and weightbearing dorsiflexion ROM predicts recurrent noncontact LAS.

Methods: A total of 191 athletes were assessed during the preseason for factors predictive of noncontact LAS. The baseline measurements included weightbearing dorsiflexion range of motion (ROM), leg-heel angle, foot internal rotation angle in plantar flexion, classification according to the mortise test, and navicular-medial malleolus (NMM) distance. Occurrence of noncontact LAS and participation in practice and games were prospectively recorded for 11 months.

Results: Of the 191 athletes assessed, 169 (145 males, 24 females) completed the study; 125 athletes had a history of ankle sprain. During the observational period, 16 athletes suffered noncontact LAS (0.58 per 1000 athlete-exposures) consisting of 4 initial sprains and 12 recurrences. The hazard ratio estimated by a Cox regression analysis showed that athletes with an NMM distance ≥4.65 cm were 4.14 times more likely to suffer an initial noncontact LAS than were athletes with a shorter NMM distance (95% confidence interval, 1.12-14.30) and that athletes with a weightbearing dorsiflexion ROM >49.5° were 1.12 times as likely to suffer a recurrent noncontact LAS compared with athletes with a lower ROM (95% confidence interval, 1.05-1.20).